Culmination of joint effort to enhance data

WASHINGTON — The small size of the revision in the 2008 flour production from the preliminary figures released in February represents the culmination of a number of steps taken in recent years to enhance the accuracy of flour production data, said James M. Hinckley, supervisory survey statistician (section chief), Bureau of the Census, U.S. Department of Commerce.

In the Flour Milling Products Summary, 2008 flour production was estimated at 416,283,000 cwts, down 1,000 cwts from the preliminary figure available in February with the release of fourth quarter flour production data.

In addition to a rise in the number of millers filling out the quarterly flour production forms, Mr. Hinckley cited other important changes that have improved the overall accuracy of the data.

For several years, the Census Bureau has been supported in the gathering of the data with funding from the North American Millers’ Association. Coincident with this funding has been increased communication about the data between the bureau and NAMA as well as with editors at Milling & Baking News who closely track this information.

A principal reason for the smaller revision has been a reduction in the estimation by the Census Bureau, Mr. Hinckley said. For many years, forms accounting for roughly 75% of flour production were submitted to the bureau each quarter. To issue its quarterly reports, the bureau imputes production for mills that do not submit forms, using historical data as well as trends from companies that were submitting.

"The imputing accounted for much of the subsequent revisions," Mr. Hinckley said. "Now, we are well over 90% on the number of people reporting to us quarterly."

Mr. Hinckley said the Census Bureau has reached out to companies to encourage them to send information quarterly. Jane DeMarchi, director of government relations at NAMA, helped provide the Census with updated company contacts while encouraging millers to participate in the data gathering more fully.

Beyond the imputation, other developments raised industry concerns about the accuracy of the flour production data. During the 1990s, the bureau announced that it had for many years failed to include in its data production from durum mills that are integrated with pasta plants. Those mills now are being included. Other anomalies in flour data also came to light and appear to have been addressed.

Milling & Baking News encouraged the bureau to check incoming data on a mill by mill basis to ensure that the figures were plausible. For example, formulas were provided to help the bureau ensure that production was in line with a mill’s capacity or that flour and millfeed production corresponded closely enough to wheat grind.

"After talks with you and the association, we were able to identify some formulas for ratios which helped us understand what kind of numbers are unrealistic or impossible," Mr. Hinckley said. "It allowed us to go to companies and say, ‘This looks like you’re producing more than you are capable of producing.’ So they would look again at the figures and adjust some numbers."

The discussions also resulted in a large scale reorganization of how state production was reported. The changes put certain groups of states together to minimize the proportion of flour production reported in the "All other states" category.

Asked what it will take to avoid a backslide in the quality of the data, Mr. Hinckley said the greatest vulnerability occurs when there are staffing changes among those who deal with the data, either at the Census Bureau or at milling companies.

Mr. Hinckley himself, who was section chief in charge of milling for five years, was recently moved to another group and has been helping with the milling report until a permanent replacement is hired. Ian Hull is the survey statistician responsible for preparing the report. Tenure in this position has ranged between one and two years in the recent past.

"For our part, keeping up will require passing along the proper information, documenting processes and maintaining close communication with NAMA and Milling & Baking News," he said. "Our biggest problems come when someone at a company switches, someone who may not know exactly what’s going on, what to look for in the data."

Mr. Hinckley encouraged millers to inform the bureau when personnel who handle the data change. Because this data in the past often had been transmitted from company accounts to government bureaucrats, parties frequently with little understanding of milling, there was a risk of data errors.

"Ideally, people reporting to us have a familiarity with the data," he said. "Absent that, perhaps there could be some oversight from someone with that knowledge. One quick page, an information sheet could help them understand something to the effect, ‘If you plug this number into this formula, it is unrealistic for the data to be outside certain parameters.’"